Another law-enforcement source tells me CAIR and other groups have been worse than useless: To this source’s knowledge, US Muslims have played virtually no role in foiling local plots.

Indeed, in some places, imams have reportedly withheld useful info and threatened to oust congregants who aid law-enforcement. Officials say Ahmad Afzali, the Queens imam helping agents probe Najibullah Zazi (the coffee vendor charged in a New York terror plot), later double-crossed them and alerted Zazi.

“I know of no investigations” in which Muslims have been helpful, Rep. Peter King (R-LI), the ranking member of the House Homeland Security Committee, tells me. He says law-enforcement and counterterror officials invariably tell him Muslim cooperation doesn’t exist. Sometimes agents say they’re met with hostility.

For folks who “understand the nature of the threat” and watch officials from “CAIR and the Muslim Public Affairs Council on major [TV] networks, it’s incredibly demoralizing,” a former FBI special agent says.

We’ve covered CAIR’s intentions to teach Muslims not to cooperate with law enforcement investigations numerous times, and the book “Muslim Mafia” also reported the same thing, from Chapter Six:

“That’s pretty interesting, because I know the FBI can’t point to one time – not even one time – when this [Muslim] outreach program has produced any information that’s of investigative value,” says a senior FBI special agent, who works counterterrorism cases…

The agent says cooperation is a one-way street with CAIR and other Muslim groups. The FBI listens and responds to their complaints, but they don’t return the favor.

Detroit Congressman John Conyers has joined ranks with CAIR and other Muslim leaders to use the death of Luqman Abdullah as a means of blunting FBI counterterrorism efforts.

Conyers’s call for an investigation of the FBI by the Civil Rights Division is aimed solely at chilling FBI efforts to get a look at what’s going on inside the Muslim community. This fits in nicely with CAIR’s longtime campaign to keep Muslims from cooperating with the FBI at all.